follow_tcp

THE RISK

Low Risk

Why follow_tcp needs a policy

This tool reads and extracts data from captured network traffic (TCP streams). While it does not modify the pcap files or network behavior, it could expose sensitive application-layer data (passwords, API keys, personal information) flowing through the captured traffic, warranting a medium severity rating.

From the tool's definition Tool name 'follow_tcp' and description 'Follow a TCP stream by index and return its ASCII payload' indicates retrieval of packet stream data without modification.

Documented attack patterns abuse exactly the kind of access follow_tcp gives an agent:

POLICY

How to control follow_tcp

PolicyLayer is an MCP gateway — it sits between your AI agents and Mcp Wireshark, and nothing reaches the server without passing your rules. This is the rule we recommend for follow_tcp:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "follow_tcp": {}
  }
}

follow_tcp is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.

Create a free account and register Mcp Wireshark — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

CAP THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Mcp Wireshark tools

Execute protocol_stats Run a tshark Execute live_capture Capture live network traffic from an interface. Writes to a Write export_json Export packets from a pcap file to a JSON file at output_path. Read check_installation Check if Wireshark/tshark is installed and return version info. Read decode_protocol Extract protocol-specific fields from a pcap file using tshark Read display_filter Apply a Wireshark display filter to a pcap file and return a Read expert_info Run tshark expert analysis on a pcap file. Returns warnings, errors, Read follow_udp Follow a UDP stream by index and return its ASCII payload.

All 13 Mcp Wireshark tools →

Read tools on other servers

M-Team MCP Server get_torrent_detail YouTube MCP Server search_channel Android Forensics ADB MCP Server parse_browser_history 0xarchive web3_challenge

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Data exfiltration → How read access becomes an exfiltration channel when chained with untrusted content.
MCP token cost → What connecting this server costs in context-window tokens on every request.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about follow_tcp

What does the follow_tcp tool do? +

Follow a TCP stream by index and return its ASCII payload. It is categorised as a Read tool in the Mcp Wireshark MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on follow_tcp? +

Register the Mcp Wireshark MCP server in PolicyLayer and add a rule for follow_tcp: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Mcp Wireshark. Nothing to install.

What risk level is follow_tcp? +

follow_tcp is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit follow_tcp? +

Yes. Add a rate_limit block to the follow_tcp rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block follow_tcp completely? +

Set action: deny in the PolicyLayer policy for follow_tcp. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides follow_tcp? +

follow_tcp is provided by the Mcp Wireshark MCP server (khuynh22/mcp-wireshark). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Mcp Wireshark tool call.

Start from Mcp Wireshark, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →